Brutal. That's the only way you can describe an episode of "The Walking Dead" that kills off two major characters in a shocking reminder of just how nightmarish this world is.The events of tonight's installment are even more tragic if you remember a few basic things:- Rick wanted to find a safe place for Lori to have her baby. He thought the prison was that place.- Rick was determined to keep his group safe from the prisoners. He thought killing Tomas and locking Andrew in a courtyard full of walkers would achieve that.- Carol was practicing to assist Lori in a C-section delivery.- Carl was still angry at his mother because of her affair with Shane.- Lori was the one who saved the life of Maggie's father, Hershel, when it seemed like all hope was lost.And the events are even more frustrating if you acknowledge one thing that's (arguably) beyond the show's control: A lot...